AbstractThe goal of the paper is to test the fast-routine EC numerical code RAD-Upgrade and the ray-tracing ABSORB-MC code for plasmas in small, average and large tokamaks and to evaluate the possibilities to combine these codes with the transport code ASTRA. This seems to be the first step in the self-consistent treatment of both the EC radiation transport and the global plasma equilibrium and heat transport in tokamak plasmas. The possibilities of the EC codes are demonstrated for various plasma conditions, namely, Russian tokamaks T-10, Tuman-3, T-14, and average size tokamak T-15, with further application to estimations of EC diagnostics possibilities on large tokamaks, including DIII-D and International thermonuclear experimental reactor (ITER).